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.\" Author: Thomas E. Dickey 1997
.\"
.\" $Id: define_key.3x,v 1.42 2024/03/16 15:35:01 tom Exp $
.TH define_key 3NCURSES 2024-03-16 "ncurses 6.5" "Library calls"
.SH NAME
\fB\%define_key\fP \-
define a \fIcurses\fR keycode
.SH SYNOPSIS
.nf
\fB#include <curses.h>
.PP
\fBint define_key(const char *\fIdefinition\fP, int \fIkeycode\fP);
.fi
.SH DESCRIPTION
This is an extension to the \fIcurses\fP library.
It permits an application to define keycodes with their corresponding control
strings,
so that the \fI\%ncurses\fP library will interpret them just as it would
the predefined codes in the terminfo database.
.PP
If \fIdefinition\fP is \fBNULL\fP,
any existing one for the keycode is removed.
Similarly, if the given keycode is negative or zero, any existing string
for the given definition is removed.
.SH RETURN VALUE
Either \fIkeycode\fP must be greater than zero,
or \fIdefinition\fP must be non-\fBNULL\fP,
otherwise \fBERR\fP is returned.
\fBERR\fP may also be returned if there is insufficient memory to allocate the
data to store the definition.
If no error is detected, \fBOK\fP is returned.
.SH PORTABILITY
These routines are specific to \fI\%ncurses\fP.
They were not supported on
Version 7, BSD or System V implementations.
It is recommended that
any code depending on them be conditioned using \fB\%NCURSES_VERSION\fP.
.SH AUTHORS
Thomas Dickey
.SH SEE ALSO
\fB\%keyok\fP(3NCURSES),
\fB\%key_defined\fP(3NCURSES)
